We propose to study the basic chemical mechanisms governing learning, memory, and behavior by investigating the structure of brain peptides by physio-chemical means, especially NMR spectroscopy. The peptides which produce these effects are produced in the pituitary gland where they are packaged, cleaved, and secreted; they then bind specifically to target membranes. We propose to isolate these neurosecretory granules and to study their storage and release. These triggering events involve proteolytic enzymes. By understanding the peptides and proteases which produce and destroy them, we propose to build up a pharmacology of these important peptides and establish methods of achieving this end.